#229: Yet more sq diff implementation. (#237)

* sq config edit: fixed glaring bug that prevented editing a source

* Refine sq diff

CHANGELOG.md

@@ -33,6 +33,17 @@ The major feature is the long-gestating `sq diff`.
   complex data in some property values.
 - CSV format now renders byte sequences as `[777 bytes]` instead of dumping
   the raw bytes.
+- ☢️ TSV format (`--tsv`) no longer has a shorthand form `-T`. Apparently that
+  shorthand wasn't used much, and `-T` is needed elsewhere.
+- ☢️ Likewise, `--xml` no longer has shorthand `-X`.
+- In addition to the format flags `--text`, `--json`, etc., there is now
+  a `--format=FORMAT` flag, e.g. `--format=json`. This will allow `sq` to
+  continue to expand the number of output formats, without needing to have
+  a dedicated flag for each format.
+
+## Fixed
+
+- `sq config edit @source` was failing to save any edits.
 
 ## [v0.35.0] - 2023-05-10
 

cli/cli.go

@@ -247,6 +247,7 @@ func hasMatchingChildCommand(cmd *cobra.Command, s string) bool {
 
 // addCmd adds the command returned by cmdFn to parentCmd.
 func addCmd(ru *run.Run, parentCmd, cmd *cobra.Command) *cobra.Command {
+	cmd.DisableFlagsInUseLine = true
 	cmd.Flags().SortFlags = false
 	cmd.PersistentFlags().SortFlags = false
 

cli/cmd_config_edit.go

@@ -180,7 +180,7 @@ func execConfigEditSource(cmd *cobra.Command, args []string) error {
 	}
 
 	src2 := &source.Source{}
-	if err = ioz.UnmarshallYAML(after, &src2); err != nil {
+	if err = ioz.UnmarshallYAML(after, src2); err != nil {
 		return err
 	}
 

cli/cmd_diff.go

@@ -25,11 +25,11 @@ var OptDiffNumLines = options.NewInt(
 )
 
 var OptDiffDataFormat = format.NewOpt(
-	"diff.data-format",
-	"data-format",
+	"diff.data.format",
+	"format",
 	'f',
 	format.Text,
-	"Diff data format",
+	"Output format (json, csv…) when comparing data",
 	`Specify the output format to use when comparing table data.
 Available formats:
 
@@ -49,8 +49,8 @@ var diffFormats = []format.Format{
 
 var allDiffElementsFlags = []string{
 	flag.DiffAll,
-	flag.DiffSummary,
-	flag.DiffTable,
+	flag.DiffOverview,
+	flag.DiffSchema,
 	flag.DiffDBProps,
 	flag.DiffRowCount,
 	flag.DiffData,
@@ -58,66 +58,103 @@ var allDiffElementsFlags = []string{
 
 func newDiffCmd() *cobra.Command {
 	cmd := &cobra.Command{
-		Use:   "diff @HANDLE1[.TABLE] @HANDLE2[.TABLE]",
-		Short: "Compare sources, or tables",
-		Long: `BETA: Compare sources, or tables.
+		Use:   "diff @HANDLE1[.TABLE] @HANDLE2[.TABLE] [--data]",
+		Short: "BETA: Compare sources, or tables",
+		Long: `BETA: Compare the metadata or row data of sources or tables.
 
-When comparing sources, by default the source summary, table structure,
-and table row counts are compared.
+CAUTION: This feature is in BETA testing. Please report any issues:
 
-When comparing tables, by default the table structure and table row counts
-are compared.
+  https://github.com/neilotoole/sq/issues/new/choose
+
+When comparing sources ("source diff"), by default the source overview, schema,
+and table row counts are compared. Row data is not compared.
+
+When comparing tables ("table diff"), by default the table schema and table
+row counts are compared. Row data is not compared.
 
 Use flags to specify the elements you want to compare. See the examples.
-Note that --summary and --dbprops only apply to source diff, not table diff.
+
+Flag --data diffs the values of each row in the compared tables. Use with
+caution with large tables.
+
+Use --format with --data to specify the format to render the diff records.
+Line-based formats (e.g. "text" or "jsonl") are often the most ergonomic,
+although "yaml" may be preferable for comparing column values. The
+available formats are:
+
+  text, csv, tsv,
+  json, jsona, jsonl,
+  markdown, html, xml, yaml
+
+The default format can be changed via:
+
+  $ sq config set diff.data.format
+
+The --format flag only applies with data diffs (--data). Metadata diffs are
+always output in YAML.
+
+Note that --overview and --dbprops only apply to source diffs, not table diffs.
 
 Flag --unified (-U) controls the number of lines to show surrounding a diff.
-The default can be changed via "sq config set diff.lines".`,
+The default (3) can be changed via:
+
+  $ sq config set diff.lines`,
 		Args: cobra.ExactArgs(2),
 		ValidArgsFunction: (&handleTableCompleter{
 			handleRequired: true,
 			max:            2,
 		}).complete,
 		RunE: execDiff,
-		Example: `  # Diff sources (compare default elements).
+		Example: `
+  Metadata diff
+  -------------
+
+  # Diff sources (compare default elements).
   $ sq diff @prod/sakila @staging/sakila
 
   # As above, but show 7 lines surrounding each diff.
   $ sq diff @prod/sakila @staging/sakila -U7
 
-  # Diff sources, but only compare source summary.
-  $ sq diff @prod/sakila @staging/sakila --summary
+  # Diff sources, but only compare source overview.
+  $ sq diff @prod/sakila @staging/sakila --overview
 
-  # Compare source summary, and DB properties.
-  $ sq diff @prod/sakila @staging/sakila -sp
+  # Diff sources, but only DB properties.
+  $ sq diff @prod/sakila @staging/sakila --dbprops
+
+  # Compare source overview, and DB properties.
+  $ sq diff @prod/sakila @staging/sakila -OP
+
+  # Diff sources, but only compare schema.
+  $ sq diff @prod/sakila @staging/sakila --schema
 
   # Compare schema table structure, and row counts.
-  $ sq diff @prod/sakila @staging/sakila --Tc
+  $ sq diff @prod/sakila @staging/sakila --SN
 
-  # Compare everything, including table data. Caution: this can be slow.
+  # Compare the data of each table. Caution: may be slow.
+  $ sq diff @prod/sakila @staging/sakila --data
+
+  # Compare everything, including table data. Caution: can be slow.
   $ sq diff @prod/sakila @staging/sakila --all
 
-  # Compare actor table in prod vs staging
+  # Compare metadata of actor table in prod vs staging
   $ sq diff @prod/sakila.actor @staging/sakila.actor
 
-  # Compare data in the actor tables. Caution: this can be slow.
-  $ sq diff @prod/sakila.actor @staging/sakila.actor --data`,
+  Row data diff
+  -------------
+
+  # Compare data in the actor tables. Caution: can be slow.
+  $ sq diff @prod/sakila.actor @staging/sakila.actor --data
+
+  # Compare data in the actor tables, but output in JSONL.
+  $ sq diff @prod/sakila.actor @staging/sakila.actor --data --format jsonl`,
 	}
 
 	addOptionFlag(cmd.Flags(), OptDiffNumLines)
 	addOptionFlag(cmd.Flags(), OptDiffDataFormat)
-	panicOn(cmd.RegisterFlagCompletionFunc(
-		OptDiffDataFormat.Flag(),
-		completeStrings(-1, stringz.Strings(diffFormats)...),
-	))
 
-	cmd.Flags().BoolP(flag.Header, flag.HeaderShort, true, flag.HeaderUsage)
-	cmd.Flags().BoolP(flag.NoHeader, flag.NoHeaderShort, false, flag.NoHeaderUsage)
-	cmd.MarkFlagsMutuallyExclusive(flag.Header, flag.NoHeader)
-
-	cmd.Flags().BoolP(flag.DiffSummary, flag.DiffSummaryShort, false, flag.DiffSummaryUsage)
+	cmd.Flags().BoolP(flag.DiffOverview, flag.DiffOverviewShort, false, flag.DiffOverviewUsage)
 	cmd.Flags().BoolP(flag.DiffDBProps, flag.DiffDBPropsShort, false, flag.DiffDBPropsUsage)
-	cmd.Flags().BoolP(flag.DiffTable, flag.DiffTableShort, false, flag.DiffTableUsage)
+	cmd.Flags().BoolP(flag.DiffSchema, flag.DiffSchemaShort, false, flag.DiffSchemaUsage)
 	cmd.Flags().BoolP(flag.DiffRowCount, flag.DiffRowCountShort, false, flag.DiffRowCountUsage)
 	cmd.Flags().BoolP(flag.DiffData, flag.DiffDataShort, false, flag.DiffDataUsage)
 	cmd.Flags().BoolP(flag.DiffAll, flag.DiffAllShort, false, flag.DiffAllUsage)
@@ -128,6 +165,11 @@ The default can be changed via "sq config set diff.lines".`,
 		cmd.MarkFlagsMutuallyExclusive(flag.DiffAll, nonAllFlags[i])
 	}
 
+	panicOn(cmd.RegisterFlagCompletionFunc(
+		OptDiffDataFormat.Flag(),
+		completeStrings(-1, stringz.Strings(diffFormats)...),
+	))
+
 	return cmd
 }
 
@@ -184,9 +226,9 @@ func getDiffSourceElements(cmd *cobra.Command) *diff.Elements {
 	if !isAnyDiffElementsFlagChanged(cmd) {
 		// Default
 		return &diff.Elements{
-			Summary:      true,
+			Overview:     true,
 			DBProperties: false,
-			Table:        true,
+			Schema:       true,
 			RowCount:     true,
 			Data:         false,
 		}
@@ -194,18 +236,18 @@ func getDiffSourceElements(cmd *cobra.Command) *diff.Elements {
 
 	if cmdFlagChanged(cmd, flag.DiffAll) {
 		return &diff.Elements{
-			Summary:      true,
+			Overview:     true,
 			DBProperties: true,
-			Table:        true,
+			Schema:       true,
 			RowCount:     true,
 			Data:         true,
 		}
 	}
 
 	return &diff.Elements{
-		Summary:      cmdFlagIsSetTrue(cmd, flag.DiffSummary),
+		Overview:     cmdFlagIsSetTrue(cmd, flag.DiffOverview),
 		DBProperties: cmdFlagIsSetTrue(cmd, flag.DiffDBProps),
-		Table:        cmdFlagIsSetTrue(cmd, flag.DiffTable),
+		Schema:       cmdFlagIsSetTrue(cmd, flag.DiffSchema),
 		RowCount:     cmdFlagIsSetTrue(cmd, flag.DiffRowCount),
 		Data:         cmdFlagIsSetTrue(cmd, flag.DiffData),
 	}
@@ -215,21 +257,21 @@ func getDiffTableElements(cmd *cobra.Command) *diff.Elements {
 	if !isAnyDiffElementsFlagChanged(cmd) {
 		// Default
 		return &diff.Elements{
-			Table:    true,
+			Schema:   true,
 			RowCount: true,
 		}
 	}
 
 	if cmdFlagChanged(cmd, flag.DiffAll) {
 		return &diff.Elements{
-			Table:    true,
+			Schema:   true,
 			RowCount: true,
 			Data:     true,
 		}
 	}
 
 	return &diff.Elements{
-		Table:    cmdFlagIsSetTrue(cmd, flag.DiffTable),
+		Schema:   cmdFlagIsSetTrue(cmd, flag.DiffSchema),
 		RowCount: cmdFlagIsSetTrue(cmd, flag.DiffRowCount),
 		Data:     cmdFlagIsSetTrue(cmd, flag.DiffData),
 	}

cli/cmd_ping.go

@@ -73,7 +73,7 @@ The exit code is 1 if ping fails for any of the sources.`,
 	addTextFlags(cmd)
 	cmd.Flags().BoolP(flag.JSON, flag.JSONShort, false, flag.JSONUsage)
 	cmd.Flags().BoolP(flag.CSV, flag.CSVShort, false, flag.CSVUsage)
-	cmd.Flags().BoolP(flag.TSV, flag.TSVShort, false, flag.TSVUsage)
+	cmd.Flags().Bool(flag.TSV, false, flag.TSVUsage)
 	cmd.Flags().BoolP(flag.Compact, flag.CompactShort, false, flag.CompactUsage)
 
 	cmd.Flags().Duration(flag.PingTimeout, time.Second*10, flag.PingTimeoutUsage)

cli/cmd_root.go

@@ -14,72 +14,75 @@ func newRootCmd() *cobra.Command {
 		Short: "sq",
 		Long: `sq is a swiss-army knife for wrangling data.
 
+  $ sq '@sakila_pg | .actor | .first_name, .last_name | .[0:10]' --json
+
 Use sq to query Postgres, SQLite, SQLServer, MySQL, CSV, Excel, etc,
-and output in text, JSON, CSV, Excel and so on, or
-write output to a database table.
+and output in text, JSON, CSV, Excel and so on, or write output to a
+database table.
 
 You can query using sq's own jq-like syntax, or in native SQL.
 
 Use "sq inspect" to view schema metadata. Use the "sq tbl" commands
-to copy, truncate and drop tables.
+to copy, truncate and drop tables. Use "sq diff" to compare source metadata
+and row data.
 
 See docs and more: https://sq.io`,
-		Example: `  # pipe an Excel file and output the first 10 rows from sheet1
-  $ cat data.xlsx | sq '.sheet1 | .[0:10]'
-
-  # add Postgres source identified by handle @sakila_pg
+		Example: `# Add Postgres source identified by handle @sakila_pg
   $ sq add --handle=@sakila_pg 'postgres://user:pass@localhost:5432/sakila'
 
-  # add SQL Server source; will have generated handle @sakila_mssql
-  $ sq add 'sqlserver://user:pass@localhost?database=sakila'
-
-  # list available data sources
+  # List available data sources.
   $ sq ls
 
-  # ping all data sources
-  $ sq ping all
-
-  # set active data source
+  # Set active data source.
   $ sq src @sakila_pg
 
-  # get specified cols from table address in active data source
-  $ sq '.address |  .address_id, .city, .country'
+  # Get specified cols from table address in active data source.
+  $ sq '.actor | .actor_id, .first_name, .last_name'
 
-  # get metadata (schema, stats etc) for data source
+  # Ping a data source.
+  $ sq ping @sakila_pg
+
+  # View metadata (schema, stats etc) for data source.
   $ sq inspect @sakila_pg
 
-  # get metadata for a table
-  $ sq inspect @pg1.person
+  # View metadata for a table.
+  $ sq inspect @sakila_pg.actor
 
-  # output in JSON
-  $ sq -j '.person | .uid, .username, .email'
+  # Output all rows from 'actor' table in JSON.
+  $ sq -j .actor
 
-  # output in text format (with header)
-  $ sq -th '.person | .uid, .username, .email'
+  # Alternative way to specify format.
+  $ sq --format json .actor
 
-  # output in text format (no header)
-  $ sq -t '.person | .uid, .username, .email'
+  # Output in text format (with header).
+  $ sq -th .actor
 
-  # output to a HTML file
-  $ sq --html '@sakila_sl3.actor' -o actor.html
+  # Output in text format (no header).
+  $ sq -tH .actor
 
-  # join across data sources
+  # Output to a HTML file.
+  $ sq --html '@sakila_pg.actor' -o actor.html
+
+  # Join across data sources.
   $ sq '@my1.person, @pg1.address | join(.uid) | .username, .email, .city'
 
-  # insert query results into a table in another data source
+  # Insert query results into a table in another data source.
   $ sq --insert=@pg1.person '@my1.person | .username, .email'
 
-  # execute a database-native SQL query, specifying the source
+  # Execute a database-native SQL query, specifying the source.
   $ sq sql --src=@pg1 'SELECT uid, username, email FROM person LIMIT 2'
 
-  # copy a table (in the same source)
-  $ sq tbl copy @sakila_sl3.actor .actor2
+  # Copy a table (in the same source).
+  $ sq tbl copy @sakila_pg.actor .actor2
 
-  # truncate tables
-  $ sq tbl truncate @sakila_sl3.actor2
+  # Truncate table.
+  $ sq tbl truncate @sakila_pg.actor2
 
-  # drop table
-  $ sq tbl drop @sakila_sl3.actor2`,
+  # Drop table.
+  $ sq tbl drop @sakila_pg.actor2
+
+  # Pipe an Excel file and output the first 10 rows from sheet1
+  $ cat data.xlsx | sq '.sheet1 | .[0:10]'`,
 	}
 
 	cmd.Flags().SortFlags = false

cli/cmd_slq.go

@@ -5,6 +5,8 @@ import (
 	"fmt"
 	"strings"
 
+	"github.com/neilotoole/sq/cli/output/format"
+
 	"github.com/neilotoole/sq/cli/run"
 
 	"github.com/neilotoole/sq/libsq/core/lg/lga"
@@ -347,21 +349,18 @@ func addTextFlags(cmd *cobra.Command) {
 	cmd.MarkFlagsMutuallyExclusive(flag.Header, flag.NoHeader)
 }
 
-// addQueryCmdFlags sets the common flags for the slq/sql commands.
+// addQueryCmdFlags sets the common flags for the slq and sql commands.
 func addQueryCmdFlags(cmd *cobra.Command) {
-	addTextFlags(cmd)
-	cmd.Flags().BoolP(flag.JSON, flag.JSONShort, false, flag.JSONUsage)
-	cmd.Flags().BoolP(flag.JSONA, flag.JSONAShort, false, flag.JSONAUsage)
-	cmd.Flags().BoolP(flag.JSONL, flag.JSONLShort, false, flag.JSONLUsage)
-	cmd.Flags().BoolP(flag.CSV, flag.CSVShort, false, flag.CSVUsage)
-	cmd.Flags().BoolP(flag.TSV, flag.TSVShort, false, flag.TSVUsage)
-	cmd.Flags().Bool(flag.HTML, false, flag.HTMLUsage)
-	cmd.Flags().Bool(flag.Markdown, false, flag.MarkdownUsage)
-	cmd.Flags().BoolP(flag.Raw, flag.RawShort, false, flag.RawUsage)
-	cmd.Flags().BoolP(flag.XLSX, flag.XLSXShort, false, flag.XLSXUsage)
-	cmd.Flags().BoolP(flag.XML, flag.XMLShort, false, flag.XMLUsage)
-	cmd.Flags().BoolP(flag.YAML, flag.YAMLShort, false, flag.YAMLUsage)
-	cmd.Flags().BoolP(flag.Compact, flag.CompactShort, false, flag.CompactUsage)
+	addOptionFlag(cmd.Flags(), OptFormat)
+	panicOn(cmd.RegisterFlagCompletionFunc(
+		OptFormat.Flag(),
+		completeStrings(-1, stringz.Strings(format.All())...),
+	))
+	addResultFormatFlags(cmd)
+	cmd.MarkFlagsMutuallyExclusive(append(
+		[]string{OptFormat.Flag()},
+		flag.OutputFormatFlags...,
+	)...)
 
 	addTimeFormatOptsFlags(cmd)
 
@@ -384,6 +383,28 @@ func addQueryCmdFlags(cmd *cobra.Command) {
 	panicOn(cmd.RegisterFlagCompletionFunc(flag.CSVDelim, completeStrings(-1, csv.NamedDelims()...)))
 }
 
+// addResultFormatFlags adds the individual flags that control result
+// output format, e.g. --text, --json, --csv, etc. It does not add
+// the --format flag, because not every command treats that flag the same.
+func addResultFormatFlags(cmd *cobra.Command) {
+	addTextFlags(cmd)
+	cmd.Flags().BoolP(flag.JSON, flag.JSONShort, false, flag.JSONUsage)
+	cmd.Flags().BoolP(flag.JSONA, flag.JSONAShort, false, flag.JSONAUsage)
+	cmd.Flags().BoolP(flag.JSONL, flag.JSONLShort, false, flag.JSONLUsage)
+	cmd.Flags().BoolP(flag.CSV, flag.CSVShort, false, flag.CSVUsage)
+	cmd.Flags().Bool(flag.TSV, false, flag.TSVUsage)
+	cmd.Flags().Bool(flag.HTML, false, flag.HTMLUsage)
+	cmd.Flags().Bool(flag.Markdown, false, flag.MarkdownUsage)
+	cmd.Flags().BoolP(flag.Raw, flag.RawShort, false, flag.RawUsage)
+	cmd.Flags().BoolP(flag.XLSX, flag.XLSXShort, false, flag.XLSXUsage)
+	cmd.Flags().Bool(flag.XML, false, flag.XMLUsage)
+	cmd.Flags().BoolP(flag.YAML, flag.YAMLShort, false, flag.YAMLUsage)
+
+	cmd.MarkFlagsMutuallyExclusive(flag.OutputFormatFlags...)
+
+	cmd.Flags().BoolP(flag.Compact, flag.CompactShort, false, flag.CompactUsage)
+}
+
 // extractFlagArgsValues returns a map {key:value} of predefined variables
 // as supplied via --arg. For example:
 //

cli/diff/diff.go

@@ -32,16 +32,16 @@ type Config struct {
 
 // Elements determines what source elements to compare.
 type Elements struct {
-	// Summary compares a summary of the sources.
-	Summary bool
+	// Overview compares a summary of the sources.
+	Overview bool
 
 	// DBProperties compares DB properties.
 	DBProperties bool
 
-	// Table compares table structure.
-	Table bool
+	// Schema compares table/schema structure.
+	Schema bool
 
-	// RowCount compares table row count.
+	// RowCount compares table row count when comparing schemata.
 	RowCount bool
 
 	// Data compares each row in a table. Caution: this can be slow.

cli/diff/source.go

@@ -43,7 +43,7 @@ func ExecSourceDiff(ctx context.Context, ru *run.Run, cfg *Config,
 		return err
 	}
 
-	if elems.Summary {
+	if elems.Overview {
 		srcDiff, err := buildSourceSummaryDiff(cfg, sd1, sd2)
 		if err != nil {
 			return err
@@ -64,7 +64,7 @@ func ExecSourceDiff(ctx context.Context, ru *run.Run, cfg *Config,
 		}
 	}
 
-	if elems.Table {
+	if elems.Schema {
 		tblDiffs, err := buildSourceTableDiffs(ctx, cfg, elems.RowCount, sd1, sd2)
 		if err != nil {
 			return err

cli/diff/table.go

@@ -29,7 +29,7 @@ func ExecTableDiff(ctx context.Context, ru *run.Run, cfg *Config, elems *Element
 		return err
 	}
 
-	if elems.Table {
+	if elems.Schema {
 		g, gCtx := errgroup.WithContext(ctx)
 		g.Go(func() error {
 			var gErr error

cli/flag/flag.go

@@ -87,7 +87,6 @@ const (
 	SQLQueryUsage = "Execute the SQL as a query (as opposed to statement)"
 
 	TSV      = "tsv"
-	TSVShort = "T"
 	TSVUsage = "Output TSV"
 
 	Text      = "text"
@@ -116,7 +115,6 @@ const (
 	YAMLUsage = "Output YAML"
 
 	XML      = "xml"
-	XMLShort = "X"
 	XMLUsage = "Output XML"
 
 	SkipVerify      = "skip-verify"
@@ -155,21 +153,21 @@ const (
 	LogLevel      = "log.level"
 	LogLevelUsage = "Log level: one of DEBUG, INFO, WARN, ERROR"
 
-	DiffSummary      = "summary"
-	DiffSummaryShort = "s"
-	DiffSummaryUsage = "Compare source summary"
+	DiffOverview      = "overview"
+	DiffOverviewShort = "O"
+	DiffOverviewUsage = "Compare source overview"
 
-	DiffTable      = "table"
-	DiffTableShort = "T"
-	DiffTableUsage = "Compare table structure"
+	DiffSchema      = "schema"
+	DiffSchemaShort = "S"
+	DiffSchemaUsage = "Compare schema structure"
 
 	DiffDBProps      = "dbprops"
-	DiffDBPropsShort = "p"
+	DiffDBPropsShort = "P"
 	DiffDBPropsUsage = "Compare DB properties"
 
 	DiffRowCount      = "count"
-	DiffRowCountShort = "c"
-	DiffRowCountUsage = "When comparing tables, include row counts"
+	DiffRowCountShort = "N"
+	DiffRowCountUsage = "When comparing table schema structure, include row counts"
 
 	DiffData      = "data"
 	DiffDataShort = "d"
@@ -179,3 +177,19 @@ const (
 	DiffAllShort = "a"
 	DiffAllUsage = "Compare everything (caution: may be slow)"
 )
+
+// OutputFormatFlags is the set of flags that control output format.
+var OutputFormatFlags = []string{
+	Text,
+	JSON,
+	JSONA,
+	JSONL,
+	CSV,
+	TSV,
+	HTML,
+	Markdown,
+	Raw,
+	XLSX,
+	XML,
+	YAML,
+}

cli/output.go

@@ -47,8 +47,8 @@ to certain formats, such as "text" or "csv".`,
 
 	OptFormat = format.NewOpt(
 		"format",
-		"",
-		0,
+		"format",
+		'f',
 		format.Text,
 		"Output format",
 		`Specify the output format. Some formats are only implemented for a subset of

cli/output/csvw/csvw.go

@@ -86,7 +86,9 @@ func (w *RecordWriter) WriteRecords(recs []record.Record) error {
 
 	if w.needsHeader {
 		headerRow := w.recMeta.Names()
-
+		for i := range headerRow {
+			headerRow[i] = w.pr.Header.Sprint(headerRow[i])
+		}
 		err := w.cw.Write(headerRow)
 		if err != nil {
 			return errz.Wrap(err, "failed to write header record")